Clarke 90EN Installation and operation manual

OPERATING & MAINTENANCE
INSTRUCTIONS
Models
90EN, 100EN, 105EN & 151EN 0502
GAS/NO-GAS MIG WELDER
GAS/NO-GAS MIG WELDER

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Thank you for purchasing this CLARKE MIG Welder, designed to operate with or
without gas....so-called GAS/NO-GAS welders. This is explained in greater detail
within the manual.
Before attempting to operate the machine, it is essential that you read this manual
thoroughly and carefully follow all instructions given. In doing so you will ensure
the safety of yourself and that of others around you, and you can also look forward
to the welder giving you long and satisfactory service.
GUARANTEE
This CLARKE product is guaranteed against faulty manufacture for a
period of 12 months from the date of purchase. Please keep your receipt
as proof of purchase.
This guarantee is invalid if the product is found to have been abused or
tampered with in any way, or not used for the purpose for which it was
intended.
Faulty goods should be returned to their place of purchase, no product
can be returned to us without prior permission.
This guarantee does not effect your statutory rights.

CONTENTS PAGE
Guarantee .............................................................................................. 3
Parts & Service Contacts ....................................................................... 3
Electromagnetic Interference (EMC) .................................................. 4
Safety Precautions ................................................................................. 6
Additional Safety Precautions for MIG Welding ............................... 11
Principles of Operation ........................................................................ 12
Electrical Connections ........................................................................ 13
Unpacking and Parts Identification ................................................... 14
Assembly ....................... Loose Components .................................... 15
Welding Shield ........................................... 15
Installing the Welding Wire ....................... 16
Selecting the Drive Roller Groove ............ 18
Converting to Gas Supply ........................ 18
Preparation for Use ....... Preparing the Work .................................... 20
Setting the Controls .................................... 20
Welding Wire Preparation .......................... 21
Attaching the Earth Lead & Clamp .......... 21
MIG Welding Operation ...................................................................... 22
Thermal Overload ...................................... 22
Welding Tips .......................................................................................... 23
Maintenance ........................................................................................ 23
Renewing the Wire Liner ............................ 24
Troubleshooting .................................................................................... 25
Control Settings Reference Tables ............................................... 26-28
Wiring Diagrams ............................................................................. 29-31
Parts Lists and Diagrams ............................................................... 32-37
Accessories .......................................................................................... 38
Parts & Service Contacts ..................................................................... 38
Welder Specifications .......................................................................... 39
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ELECTROMAGNETIC INTERFERENCE (EMC)
Whilst this unit complies with EMC regulations, the user is responsible for installing
and using the welding equipment according to the manufacturers instructions. If
electromagnetic disturbances are detected then it shall be the responsibility of
the user of the welding equipment to resolve the situation. In some cases this
remedial action may be as simple as earthing the welding circuit, see ‘Note’. In
other cases it could involve constructing an electromagnetic screen enclosing
the power source and the work complete with associated input filters. In all cases
electromagnetic disturbances must be reduced to the point where they are no
longer troublesome.
Note - The welding circuit may or may not be earthed for safety reasons. Changing
the earthing arrangements should only be authorised by a person who is
competent to assess whether the changes will increase the risk of injury, e.g. by
allowing parallel welding current return paths which may damage the earth circuits
of other equipment.
1.ASSESSMENT OF AREA
Before installing welding equipment the user shall make an assessment of potential
electromagnetic problems in the surrounding area. Avoid using your welder in the
vicinity of:
a) other supply cables, control cables, signalling and telephone cables;
above, below and adjacent to the welding equipment;
b) radio and television transmitters and receivers;
c) computer and other control equipment;
d) safety critical equipment, e.g. guarding of industrial equipment;
e) pacemakers and hearing aids etc.;
f) equipment used for calibration or measurement;
g) other equipment in the environment. The user shall ensure that other
equipment being used in the environment is compatible. This may
require additional protection measures;
It may be possible to avoid the above by changing the time of day that welding
or other activities are to be carried out.
The size of the surrounding area to be considered will depend on the structure of
the building and other activities that are taking place. The surrounding area may
extend beyond the boundaries of the premises.
2. METHODS OF REDUCING EMISSIONS
2.1 Mains supply
Welding equipment should be connected to the mains supply according to the
manufacturers recommendations. If interference occurs, it may be necessary to
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take additional precautions such as filtering of the mains supply. Consideration
should be given to shielding the supply cable of permanently installed welding
equipment, in metallic conduit or equivalent. Shielding should be electrically
continuous throughout its length. The shielding should be connected to the welding
power source so that good electrical contact is maintained between the conduit
and the welding power source enclosure.
2.2 Maintenance of the welding equipment
The welding equipment should be routinely maintained according to the
manufacturers recommendations. All access and service doors and covers should
be closed and properly fastened when the welding equipment is in operation.
The welding equipment should not be modified in any way except for those
changes and adjustments covered in the manufacturers instructions. In particular,
the spark gaps of arc striking and stabilizing devices should be adjusted and
maintained according to the manufacturers recommendations.
2.3 Welding cables
The welding cables should be kept as short as possible and should be positioned
close together, running at or close to the floor level.
2.4 Equipotential bonding
Bonding of all metallic components in the welding installation and adjacent to it
should be considered. However, metallic components bonded to the work piece
will increase the risk that the operator could receive a shock by touching these
metallic components and the electrodes at the same time. The operator should
be insulated from all such bonded metallic components.
2.5 Earthing of the workpiece
Where the workpiece is not bonded to earth for electrical safety, nor connected
to earth because of its size and position, e.g. ships hull or building steelwork, a
connection bonding the workpiece to earth may reduce emissions in some, but
not all instances.
Care should be taken to prevent the earthing of the workpiece increasing the risk
of injury to users, or damage to other electrical equipment.
Where necessary, the connection of the workpiece to earth should be made by
a direct connection to the workpiece, but in some countries where direct
connection is not permitted, the bonding should be achieved by suitable
capacitance, selected according to national regulations.
2.6 Screening and shielding
Selective screening and shielding of other cables and equipment in the surrounding
area may alleviate problems of interference. Screening of the entire welding
installation may be considered for special applications.

SAFETY PRECAUTIONS FOR ALL TYPES OF WELDING
1. WARNING:
As with all machinery, there are certain hazards involved with their operation
and use. Exercising respect and caution will considerably lessen the risk of
personal injury. However, if normal safety precautions are overlooked, or
ignored, personal injury to the operator may result.
FAILURE TO FOLLOW THESE RULES MAY RESULT IN SERIOUS PERSONAL INJURY
2. GENERAL PRECAUTIONS
A) Burn prevention
Wear protective clothing - gauntlet gloves designed for use in welding, apron, and
protective shoes. Button shirt collar and pocket flaps, and wear cuffless trousers to
avoid entry of sparks and slag. Wear helmet with safety goggles or glasses with side
shields underneath, appropriate filter lenses or plates (protected by clear cover
glass). This is a MUST for welding or cutting, (and chipping) to protect the eyes from
radiant energy and spatter. Replace cover glass when broken, pitted, or spattered.
Avoid oily greasy clothing. A spark may ignite them. Hot metal such as electrode
stubs and workpieces should never be handled without gloves. First aid facilities
and a qualified first aid person should be available unless medical facilities are close
by for immediate treatment of flash burns of the eyes and skin burns. Ear plugs
should be worn when working overhead or in a confined space. A hard hat should
be worn when others work overhead. Flammable hair preparations should not be
used by persons intending to weld or cut.
B) Toxic fume prevention
Severe discomfort, illness or death can result from fumes, vapours, heat, or oxygen
enrichment or depletion that welding (or cutting) may produce. Prevent them
with adequate ventilation. NEVER ventilate with oxygen. Lead-, cadmium-, zinc-,
mercury- and beryllium-, bearing materials, when welded (or cut) may produce
harmful concentrations of toxic fumes. Adequate local exhaust ventilation must
be used, or each person in the area as well as the operator must wear an air-
supplied respirator. For beryllium, both must be used. Metals coated with or
containing materials that emit toxic fumes should not be heated unless coating is
removed from the work surface, the area is well ventilated, or the operator wears
an air-supplied respirator. Work in a confined space only while it is being ventilated
and, if necessary, while wearing an air-supplied respirator. Vapours from
chlorinated solvents can be decomposed by the heat of the arc (or flame) to
form PHOSGENE, a highly toxic gas, and other lung and eye irritating products.
The ultraviolet (radiant) energy of the arc can also decompose trichloroethylene
and perchloroethylene vapours to form phosgene. DO NOT WELD or cut where
solvent vapours can be drawn into the welding or cutting atmosphere or where
the radiant energy can penetrate to atmospheres containing even minute
amounts of trichloroethylene or perchloroethylene.
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C) Fire and explosion prevention
Causes of fire and explosion are:
1) combustibles reached by the arc, flame, flying sparks, hot slag or heated
material;
2) misuse of compressed gases and cylinders;
3) short circuits.
BE AWARE THAT flying sparks or falling slag can pass through cracks, along pipes,
through windows or doors, and through wall or floor openings, out of sight of the
goggled operator. Sparks and slag can fly 10M.
To prevent fires and explosion: keep equipment clean and operable, free of oil,
grease, and (in electrical parts) of metallic particles that can cause short circuits.
If combustibles are in area, do NOT weld or cut. Move the work if practicable, to
an area free of combustibles.
Avoid paint spray rooms, dip tanks, storage areas, ventilators. If the work cannot
be moved, move combustibles at least 10M, away out of reach of sparks and
heat; or protect against ignition with suitable and snug fitting, fire- resistant covers
or shields.
Walls, ceilings, and floor near work should be protected by heat resistant covers
or shields. Fire watcher must be standing by with suitable fire extinguishing
equipment during and for some time after welding or cutting if:
a) appreciable combustibles (including building construction) are within 10m.
b) appreciable combustibles are further than 10m but can be ignited by sparks.
c) openings (concealed or visible) in floors or walls within 10m can expose
combustibles to sparks.
d) combustibles adjacent to walls, ceilings, roofs or metal partitions can be
ignited by radiant or conducted heat.
After work is done, check that area is free of sparks, glowing embers, and flames.
An empty container that held combustibles, or that can produce flammable or
toxic vapours when heated, must never be welded on or cut, unless container
has first been cleaned. This includes.......a thorough steam or caustic cleaning (or
a solvent or water washing, depending on the combustible’s solubility) followed
by purging and inerting with nitrogen or carbon dioxide, and using protective
equipment.
Water filling just below working level may substitute for inerting.
A container with unknown contents should be cleaned (see paragraph above),
do NOT depend on sense of smell or sight to determine if it is safe to weld or cut.
Hollow castings or containers must be vented before welding or cutting - they
can explode.
In explosive atmospheres, never weld or cut where the air may contain flammable
dust, gas, or liquid vapours.

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3. ELECTRIC ARC (MIG, TIG) WELDING
Comply with precautions in 1 above, and this section. Arc welding, properly done,
is a safe process, but a careless operator invites trouble. The equipment carries
high currents at significant voltages. The arc is very bright and hot. Sparks fly, fumes
rise, ultraviolet and infrared energy radiates, weldments are hot. The wise operator
avoids unnecessary risks and protects himself and others from accidents.
3A) BURN PROTECTION
Comply with precautions in 2. The welding arc is intense and visibly bright. Its
radiation can damage eyes, penetrate lightweight clothing, reflect from light
coloured surfaces, and burn the skin and eyes. Skin burns resemble acute sunburn,
those from gas - shielded arcs are more severe and painful.
DON’T GET BURNED! COMPLY WITH PRECAUTIONS!
1) Protective clothing
Wear long sleeved clothing (particularly for gas shielded arc) in addition to such as
leather jacket or sleeves, flameproof apron, and fire-resistant leggings. Avoid outer
garments of untreated cotton. Bare skin protection: Wear dark substantial clothing,
Button collar to protect chest and neck. Button pockets to prevent entry of sparks.
2) Eye and head protection
Protect eyes from exposure to arc. NEVER look at an electric arc without protection.
Welding helmet or shield containing a filter plate shade no. 12 or denser must be
used when welding. Place over face before striking arc. Protect filter plate with a
clear cover plate. Cracked or broken helmet or shield should NOT be worn; radiation
can pass through to cause burns. Cracked, broken, or loose filter plates must be
replaced IMMEDIATELY. Replace clear cover plate when broken, pitted, or spattered.
WE SUGGEST you wear flash goggles with side shields under the helmet, to give
some protection to the eyes should the helmet not be lowered over the face before
an arc is struck. Looking at an arc momentarily with unprotected eyes (particularly
a high intensity gas-shielded arc) can cause a retinal burn that may leave a
permanent dark area in the field of vision. Before welding whilst wearing contact
lenses, seek advice from your optician.
3) Protection of nearby personnel
For production welding, a separate room or enclosed bay is best. In open areas,
surround the operation with low reflective, non- combustible screens or panels. Allow
for free air circulation, particularly at floor level. Provide face shields for all persons
who will be looking directly at the weld. Others working in the area should wear flash
goggles. Before starting to weld, make sure that screen or bay doors are closed.

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3C) FIRE AND EXPLOSION PREVENTION
Comply with precautions in 2C. Equipment’s rated capacity. Do not overload arc
welding equipment. It may overheat cables and cause a fire. Loose cable
connections may overheat or flash and cause a fire. Never strike an arc on a cylinder
or other pressure vessel. It creates a brittle area that can cause a violent rupture or
lead to such a rupture later under rough handling.
3D) SHOCK PREVENTION
Exposed live conductors or other bare metal in the welding circuit, or in
unearthed, electrically-LIVE equipment can fatally shock a person whose
body becomes a conductor. DO NOT STAND, SIT, LIE, LEAN ON, OR TOUCH a
wet surface when welding, without suitable protection.
3E) PROTECTION FOR WEARERS OF ELECTRONIC LIFE SUPPT DEVICES (PACEMAKERS)
Magnetic fields from high currents can affect pacemaker operation. Persons wearing
electronic life support equipment (pacemaker) should consult with their doctor
before going near arc welding, gouging, or spot welding operations.
3F) TO PROTECT AGAINST SHOCK:
Keep body and clothing dry. Never work in damp area without adequate
insulation against electrical shock. Stay on a dry duckboard, or rubber mat
when dampness or sweat can not be avoided. Sweat, sea water, or moisture
between body and an electrically LIVE part - or earthed metal - reduces the
body surface electrical resistance, enabling dangerous and possibly lethal
currents to flow through the body.
1) Earthing the equipment
When arc welding equipment is earthed according to the National
Electrical Code, and the workpiece is earthed, a voltage may exist
between the electrode and any conducting object.
Examples of conducting objects include, but are not limited to, buildings,
electrical tools, work benches, welding power source cases, workpieces, etc.
Never touch the electrode and any metal object unless the welding power
source is off. When installing, connect the frames of each unit such as welding
power source, control, work table, and water circulator to the building earth.
Conductors must be adequate to carry earth currents safely. Equipment made
electrically LIVE by stray current may shock, possibly fatally. Do NOT EARTH to
electrical conduit, or to a pipe carrying ANY gas or a flammable liquid such as
oil or fuel.
2) Electrode holders
Fully insulated electrode holders should be used. Do NOT use holders
with protruding screws or with any form of damage.
3) Connectors
Fully insulated lock-type connectors should be used to join welding
cable.

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4) Cables
Frequently inspect cables for wear, cracks and damage. IMMEDIATELY
REPLACE those with excessively worn or damaged insulation to avoid
possibly lethal shock from bared cable. Cables with damaged areas may
be taped to give resistance equivalent to original cable. Keep cable dry,
free of oil and grease, and protected from hot metal and sparks.
5) Terminals and other exposed parts
Terminals and other exposed parts of electrical units should have insulating
covers secured before operation.
6) Electrode
a) Equipment with output on/off control (contactor)
Welding power sources for use with the gas metal arc welding, gas
tungsten arc welding and similar processes normally are equipped with
devices that permit on/off control of the welding power output. When
so equipped the electrode wire becomes electrically LIVE when the
power source switch is ON and welding gun switch is closed. Never
touch the electrode wire or any conducting object in contact with
the electrode circuit unless the welding power source is off.
b) Equipment without output on/off control (no contactor)
Welding power sources used with shielded metal arc welding and similar
processes may not be equipped with welding power output on/off
control devices. With such equipment the electrode is electrically LIVE
when the power switch is turned ON. Never touch the electrode unless
the welding power source is off.
7) Safety devices
Safety devices such as interlocks and circuit breakers should not be
disconnected or shunted out. Before installation, inspection, or service of
equipment, shut OFF all power and remove line fuses (or lock or red-tag
switches) to prevent accidental turning ON of power. Do not open power
circuit or change polarity while welding. If, in an emergency, it must be
disconnected, guard against shock burns, or flash from switch arcing.
Always shut OFF and disconnect all power to equipment. Power disconnect
switch must be available near the welding power source.
PREPARATION OF THE WORKING AREA
The working area must be sufficiently spacious, not humid, and well-ventilated as
to avoid any fumes which develop from the welding process and from incidental
material adhering to the pieces to be welded (oils, paints, tars...) which may cause
annoyance to the operator.
Avoid welding by contact with humid parts nearby combustible liquids. Least of
all, do not weld upon tanks which may contain flammable residuals.